AutomationDirect DL205 - Channel Update Sequence for DL240, DL250-1, and DL260 Cpus (Pointer Method)

DL205 Analog Manual, 7th Edition Rev. D
12-8
Chapter 12: F2-02DAS-1, 4-20mA Isolated 2-Channel Analog Current Output
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Channel Update Sequence for DL240, DL250-1, and DL260 CPUs
(Pointer Method)
If either a DL240, DL250-1 or DL260 CPU is used with the pointer method, all channels can
be updated on every scan. This is because the three CPUs support special V-memory locations
that are used to manage the data transfer. This is discussed in more detail in the next section
on Writing the Control Program.
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Channel1,2
Channel1,2
Channel1,2
Channel1,2
Channel1,2
Scan N
Calculatethe data
Writedata
Read inputs
ExecuteApplic ationProgram
Scan N+1
Scan N+2
Scan N+3
Scan N+4
Scan
Writeto outputs
System With
DL240/250-- 1/260
CPU